Sobradores is an adjective that describes someone who is arrogant, conceited, or acts superior. It's a less common word than 'arrogante' or 'engreído', making it more interesting and unique.
In the song, the lyrics say, "Ahí va, mírenlo, que aire sobrador" (There he goes, look at him, what an arrogant air). It perfectly captures the dismissive and haughty attitude of the wealthy man in the Rolls-Royce, highlighting his perceived superiority over others.
This song, "El Gran Señor" by Los Auténticos Decadentes with Los Nocheros, is a really interesting take on moving on from a past relationship. The singer tells us that since they no longer have to "cuidar tu cariño" [take care of your affection] or "oír tus caprichos" [listen to your whims], they "ya no sufro tanto" [don't suffer as much]. It sounds like the relationship was a lot of work!
Then, the song introduces "el gran señor" [the great lord], someone who drives a Rolls-Royce and has a very "sobrador" [arrogant] air. This new person tried to be the love that would make the ex-partner forget the singer, but the lyrics are clear: "nunca lo logró ni lo logrará" [he never achieved it, nor will he]. The rich man shared his wealth to try and get "un poco de amor, lo que nunca vos le pudiste dar" [a little love, what you could never give him]. It's a pretty blunt assessment of a relationship built on money rather than genuine affection, and the singer seems quite content to be out of that whole situation.